Hale to john



(No Model.)

G. G. MOOR.

CANNON PINION FOR WATCHES.

Patented July 20, 1886.

Mass 661 N PETERS Pholn-Limugraphnr. Waahingluh. 0.0

- UNITED STATES PATENT @FhliCE;

GEORGE l). MOOR, OF \VALTHAM, MASSACHUSETTS, ASSIGNOR OF ONE HALF TO JOHN STARK, Jlt, OF SAME PLACE.

CANNON-PINlON FOR WA'i'Cii Application filed January 19. 18"

To aZZ 1071 0722, it may concern:

Be ithnown that I, Gnoncn 0. Moon, of Waltham, county of h'liddlcsex, and State of Massachusettahaveinvented an Improvement in Friction Devices for lVatclrMovements, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

This invention has for its object to provide a watch-movement with an improved friction device, whereby the hands of the watch may be moved irrespective of the movement of the train, and yet firmly retain their relative position to be moved by the train.

In accordance with this invention the usual cannon-pinion mounted upon the arbor of the center-wheel is split or slitted diametrically, said slit extending vertically a short distance into the staff thereof, and the arbor of the center-whcel isprovided with a hub, over or upon which the slitted cannon-pinion is sprung, thereby bearing firmly upon the hub.

The invention consists in the combination of the center-wheel and its arbor, having a hub thereon,with a cannon-pinion slitted diamct rically and for a short distance vertically, to thereby permit the said cannon-pinion to be sprung over upon thehub of the eenter-wheel, all as will be hereinafter more fully described,

Figure 1 shows in plan view a portion of a watch-train constructed in accordance with this invention; l ig. 2, an enlarged transverse section of the cannon-pinion, the minute and hour wheels co-operating therewith, the center-wheel being shown in elevation; Fig. 8, an under side view of the cannon-pinion alone; Fig. 4-, a vertical section of the cannonpinion, and Fig. 5 an enlarged view of Fig. i.

The bevel-gear c, shifting-lever 1?, mainspring-gear 6, its spring-controlled pawl c,intermediate a, yoke 13, and toothed gear a are all as usual, forming component parts of a setting mechanism of a watch-movement.

The centeravheelf, (see Fig. 2,) having an arbor, f, and bottom pivot, f, is of usual construction, and is provided with ahub or boss,

j", at the portion of the arbor contiguous to the plate A and just above the bottom pivot,f",

Serial No. iSTiEfi-l. (No moel.)

that portion of the said hub or bossf next the bottom pivot, f, being somewhat reduced in diameter as compared with its opposite end.

The leaves 0 of the usual cannon-pinion are split diametrically, said slit also extending ver t-ically for a short distance into the staff a, to thereby permit the two portions of the pinion thus split to yield or separate from each other,

in order that the same may be slipped upon the arbor/ of the center-wheel and sprung over the hub or bossf', the said hub or boss f being ofsufiicientdiameter to occupy a space out in the lower end of the cannon-pinion, to thereby cause the said cannon-pinion to turn frictionally thereon with considerable resistance.

The hour-wheel m is mounted upon the can non-pinion in usual manner, and the minute wheel or, having a toothed hub, m, and mcslr ing, respectively, with the cannon-pinion and hour-wheel, is of usual construction and turns on a pivot, m.

The cannoirpinion, slitted as de'scribed,may be made to turn upon the bossf, formed on the arbor of the center-wheel, as firmly as desired, its tension being regulated by the diameter of the bossf. By constructing the hub or bossf of conical shape ortapering, as described,tliecmmou-pinion,once sprungover, cannot readily be thrown oil, unless moved positively,

By the friction devices herein described the cannon-pinion and its co-operating parts may be moved freely, yet rcsistingly, upon the an her of the centenwheel, irrespective of the movement of the train, the resistance being amply sut'licient to cause the said cannoupinion to be moved by the train.

I am aware that a cannon-pinion has been slittcd at its upper end, and the interior of the bore of the pinion has been provided with a projection which enters a groove around the stall of the center-wheel; but such construe tion I do not herein claim, as I deem it impractical because of the expense altendingits manufacture, and owing to the fact that as the hand is applied to this portion of the cannon pinion it is dillicult to construct the same so that the hand may be readily applied to the slitted end, which naturallyyields withoutinterfering with the frictional result desired.

I claim 1. In a watch-movement, the combination of the center-wheel, its arbor, and the hub or boss f thereon, contiguous to the centerwheel, with a cannon-pinion slitted diamet-- rieally at its lower end contiguous to the center-whee], and recessed, as described, and

placed upon the arbor of the said centerwheel, the slitted and recessed portion of the said cannon-pinion being sprung over and upon the said hub 0r boss f, all substantially as described. I

2. In a watch-movement, the combination of the center-whee], its arbor, and the conical Witnesses:'

BRADSHAW S. TOLMAN, ROBERT M. STARK. 

